Diagnosis Procedure
1.Check connector
Is the inspection result normal? Yes >> go to 2.
No >> repair the terminal and connector.
2.Check harness for open circuit

Is the measurement value within the specification? Yes >> go to 3.
No >> repair the eps control unit branch line.
3.Check power supply and ground circuit
Check the power supply and the ground circuit of the EPS control unit. Refer to STC-22, "Diagnosis Procedure".
Is the inspection result normal? YES (Present error)>>Replace the EPS control unit. Refer to STC-39, "Removal and Installation".
YES (Past error)>>Error was detected in the EPS control unit branch line.
NO >> Repair the power supply and the ground circuit.
Dlc branch line circuit
M&A branch line circuitPrecaution
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT
BELT PRE-TENSIONER"
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”,
used along
with a front seat belt, helps to reduce the risk or severity of injur ...
P0128 Thermostat function
DTC Logic
DTC DETECTION LOGIC
NOTE:
If DTC P0128 is displayed with DTC P0300, P0301, P0302, P0303 or P0304,
first perform the trouble
diagnosis for P0300, P0301, P0302, P0303 or P0304. Refer to EC-269, "DTC Logic".
Engine coolant temperature has not risen enough to open the thermost ...
Engine control system
Symptom Table
SYSTEM — BASIC ENGINE CONTROL SYSTEM
1 - 6: The numbers refer to the order of inspection.
(continued on next table)
SYSTEM — ENGINE MECHANICAL & OTHER
1 - 6: The numbers refer to the order of inspection. ...